1. Field of the Invention
The present invention relates to electronic household type sewing machines and more particularly to such machines having automatic control for the needle bar transverse oscillations and the feed member displacement.
2. Description of the Prior Art
Electronic sewing machines are well known which provide for control of needle bar transverse oscillations and feed member displacement. Household types sewing machines of this type which are known to the applicants generally store information relative to the needle bar and feed positions as a digital code in a read only memory or other static memory. Such a memory is merely a data bank which is conventionally sequentially explored during the execution of a predetermined sewing program beginning from the first stitch of a selected pattern to the last one of the same pattern and so on repeatedly. An example of such an arrangement is disclosed in U.S. Pat. No. 3,984,745 which is owned by the Singer Company. Moreover, the Singer Company has commercially sold a variety of such means under what Singer has commonly termed their "TOUCH-TRONIC FAMILY" which incudes the Singer Model 2001, the Singer Model 2000, the Singer Model 1200 and the Singer Model 1060. For example, the Singer Model 2001 lets the user select any of 27 preprogrammed stitch patterns by pushing the key uniquely corresponding to that pattern as well as providing automatic selection of length and width for the pattern and, if desired, the mirror image of such a pattern. This machine, as well as the other Singer machines known to the applicants, however, are confined to selection of the stored programs, or their mirror images, and do not provide sufficient flexibility to enable the user to vary the stitch pattern data, such as to maintain a constant stitch density while the length of the selected stitch pattern is varied. In addition, the applicants are not aware of any household electronic type sewing machines capable of automatically providing alphabetic stitch patterns, such as to sew monograms. Although prior art mechanical sewing machines employing elaborated camming arrangements, such as previously sold by Borletti S.P.A. of Milan, Italy have been capable of providing monograms.
Other examples of electronic sewing machines known to applicants are disclosed in Japanese Pat. No. 8675/72, issued to Matsushita Electric Ind. Co., Ltd., Japanese Pat. No. 15713/70, issued to Janome Sewing Machine Co., Ltd.; U.S. Pat. No. 3,076,066, owned by Mefina S.A.; U.S. Pat. No. 3,005,136, also owned by Mefina S.A.; U.S. Pat. No. 3,834,332, owned by Meister-Werke Gmbh; U.S. Pat. No. 3,613,608, owned by Kayser-Roth Corporation; U.S. Pat. No. 3,752,098, owned by The Gerber Scientific Instrument Company; U.S. Pat. Nos. 3,982,491; 3,986,466 and 4,051,794 owned by Union Special Corp.; U.S. Pat. Nos. 4,078,506; 4,072,114 and 4,069,778 owned by Brother Kogyo; U.S. Pat. Nos. 4,108,093 and 4,086,862 owned by Janome; U.S. Pat. No. 4,116,144 owned by Sharp Kabushiki; and U.S. Pat. No. 4,108,091 owned by Husqvarna AB. The above art is merely exemplary of a field which is becoming increasingly crowded as technology in the sewing machine field continues to convert from the mechanical age to the electronic age. Thus, by and large, the majority of prior art electronic controlled sewing machines are merely electronic conversions of their earlier mecanical equivalents which, through the use of various cam stacks, were capable of providing a plurality of selectable patterns to the operator. These cam stacks were merely replaced by their prior art electronic equivalents, namely a static memory, such as a read only memory or some other type of electronic storage. Thus, these prior art electronic solutions did not enable the processing of the stored stitch pattern data as well as operative flexibility in the use of such data, such as to create additional stitch patterns beyond those stored in the memory through the operation on the stored stitch patterns, such as for example, interpolating the stitch pattern data to enable the maintenance of a constant stitch pattern density as the length of the stitch pattern is varied while maintaining the shape of the pattern as well as the ability to select a plurality of patterns which can be alternatively combined to create a new stitch pattern arrangement or to automatically combine stitch patterns such as to provide an initial tacking stitch automatically before commencing the sewing of a straight stitch. However, the electronic sewing machine disclosed in U.S. Pat. No. 4,122,786, owned by Sharp K.K. is enable alternatively of combining stitch patterns to create a composite stitch pattern arrangement. With the advent of the microcomputer, it has gradually found its way into machine control, such as disclosed in U.S. Pat. No. 4,079,235 owned by McDonnel Douglas Corp.; U.S. Pat. No. 4,115,058 owned by Houdaille Industries, Inc. and U.S. Pat. No. 3,906,324. However none of these prior art systems economically and efficiently solves the problems of providing a totally electronic sewing machine. Moreover, the electronic controlled sewing machines known to applicants all provide keyboards in which a specific key is required for stitch patterns selection. This arrangement is not only unsatisfactory but is necessarily physically limiting to the amount of stitch patterns which can be provided in the household type sewing machine as there is only a limited amount of room for the keyboard on the machine, which is the presently preferred location for such keyboards.
These disadvantages of the prior art are overcome by the present invention.